Variable wing construction



July 30, 1946. E. F. ZAP 2,404,895

VARIABLE WING CONSTRUCTION Filed Jan. 19, 1942 2 Sheets-Sheet 1/NVENTO/Q/ EDV/4R0 ZAP omda u.,

Fm? THE F/ 2 Sheets-Sheet 2 /NVENTo/@J Eoin/ARD F ZAP /A faQ/.5, MECH]FOSTER HAR/WJ b k'" TH: HKM

E. F. ZAP

VARIABLE WING'` CONSTRUCTION Flled Jan 19, 19212 July 3o, 1946.

Patented July 30, 1946 .i

UNITED STATES PATENT oElElcEN VARIABLE WING CONSTRUCTION Edward F. Zap,Los Angeles, Calif.

Application January 19, 1942, Serial No. 427,237

8 Claims.

My invention relates to the construction ci airplane wings and moreparticularly relates to mounting and controlling relatively movableparts of variable wings. By way of example, the present invention willbe described as directed specically to improvements on the structuredisclosed in my copending application Serial No. 352,516, entitledAirplane wing construction," and the present invention will thereforehave the objects set forth in that application. It will be understood,Ahowever, that the principles exemplified herein may-be applied to othertypes of wings and features of the new construction may be employedapart from the arrangementas a whole.A

` The particular wing construction under consideration here is of thehigh lift or variable lift type that is changed in conguration in accordwith changing operating conditions. Thus, such a wing may be variedtemporarily to provide relatively high` lift for take-oit and again maybe varied to provide both increased lift and increased drag for landing.Asset forth in said copending application the variable wing of thepresent type has a hollow portion lying between trailing flap is mountedin this hollow portion for extension and retraction rearwardly anddownwardly from the wing. Preferably the ap is of curved conguration andis mounted for the wing and hence will involve no necessity for openingsthrough the rear spar. It is contemplated that the means for actuatingand controlling the aileron of the wing as well as the means foractuating andcontrolling the extensible flap of the wing will berestricted to the wing space rearward of the rear spar, neithermechanism interfering with the other.

One ofthe problems in the described wing arrangementis to provide in theconfined rearward space a structurally ecient and thoroughly reliablemechanism for actuating and controlling the iiap, such mechanism tobezfully effective at all positions of the flap. It is difficultA todesign a mechanism or linkage that does not at some point of operationbecome unwieldy or develop unfavorable leverage. One of the objects isto provide a mechanism that meets this problem and `the rearward sparand the trailing edge, and a I movement outward alonga curved path froma 7;

retracted position largely, if not entirely, inside the wing, to variouspositions of extension. To provide for an adequate range of flapmovement and yet require relatively little space for mounting means, theap is movably orretractably y mounted on a support that is itselfmovably or retractably mounted on the wing. The range of movement oi theflap in such a construction is the range'of relative movement providedbetween the flap and the support plus' the range of relative movementprovided between the support and the wing. The contemplated wingconstruction as set forth in said copending application also includes anovel aileron that is adapted to extend into or retract from the airstream above the t? wing.

One of th'e objects of the present improvement is to provide compactnessor efficient utilization of space in an airplane wing and at the sametime to 'achieve eiiiciency and dependability in the mechanism foractuating and controlling the relatively movable parts of the wing. Anarrangement is sought that may be conned enyet is adapted to thepeculiar space limitations of an airplane wing. In this aspect theinvention is characterized by a new combination of pulleys, cables,and'guide means for flap actuation.

A group of objects relating to the means for movably mounting the ap'inthe wing includes the following: to reduce` the number of movable flapsupports required in my earlier structure; to simplify the constructionof such movable supports; to avoid' loading such movable supports in anymanner tending to develop undesirable torques in the supports; toprovide an arrangement in which the movable supports are efcientlyrelated to the rib structure of the wing for transmitting loads thereto;and to provide means for movablymounting the iiap on the movablesupports in an efficient manner.

The above and other objects of the invention will be apparent in myfollowing detailed description, taken with the'accompanying drawings.

illustrative only:

Fig. 1 is a diagrammatic view of an airplane in perspective showing theprincipal elements in the system for actuating and controlling the wingflaps;

Fig. 2 is a fore-and-aft section through a wing of the airplane, boththe ap and the aileron being retracted;

Fig. 3 is a similar view with theiiap and aileron extended;

Fig. 4 is an enlarged view partly in section taken as indicated by theline 4-4 of Fig. 2;

- Fig. 5 is a section on an enlarged scale taken as indicated by theirregular line 5- 5 of Fig, 2;

In the drawings, which are to be considered as surface of the panel.

Fig. 6 is a section on an enlarged scale taken as indicated by the line6 6 of Fig. 2; and

Fig. '1 is a section on an enlarged scale taken as indicated by the line1-1 of Fig. 3.

The drawings show an airplane having a fuselage I6 and a pair of wingsII, the framework of each wing including a rear spar I2 (Fig. 2) and anumber of ribs generally designated I3 (Figs. 5 and 6). In each wing therear spar I2 and the various ribs I3 form what maybe termed hollowportions or wing compartments I5.

An aileron,

generally designated I6 is mounted in each wing Il to move upwardthrough an opening I1' (Fig. 3) in the upper skin I6 of the wing, and aflap -generally designated is mounted in the wing to move rearwardthrough an opening 2I in the trailing edge ofthe wing. A ,y

Each of the ailerons I6 comprises a plurality of aileron panels 22mounted in successive wing `compartments I5, the panels beingconnectedin a unitary manner by al common end plate or deecting plate23. Each aileron panel 22 may be of hollow construction with a l-owerwall 25 and van upper curved wall 26. The upper wall 26 provides whatmay be termed the curved effective In the present arrangement it iscontemplated that normally each of the ailerons I6 will be sbstantiallyentirely inside the corresponding wing II, with the deecting plate 23substantially flush with the wing skin I8. For rolling control of theairplane each aileron I6 is movable upward in a curved path having oneor more centers or axes of curvature lying above the wing and forward ofthe aileron. Since the wings I'I shown in Fig. 1 are of taperingplanform, the aileron panels 22 may likewise be tapered.

sides of each aileron panel in moving engageri' ment .with four ro-llers36 mounted on one of the wingiribsl I3. For actuation of the aileron I6each of the panels 22 may be provided with a small bracket plate 3l towhich is p-ivotally connected one end of an adjustable operating rod 62,

the other end of the operating rod being pivotally connected to an arm33 on an operating shaft 35. .Any suitable mechanism may be employed tocontrol the aileron-operating shafts 35 in the two Wings.

' The flap 26 may comprise a'series of flap panels 36 that areindividually mounted in successive wing compartments I5, the variouspanels being connected in a unitary manner by a common trailing member31 having an air-deflecting surface 38. The flapv 2l) is curvedincross-.sectional configuration and since the wings l l are tapered inplan form the iiap may have the o-verall configuration of a longitudinalsection of a truncated cone. The flap 20 may be adapted to move in acurved path concentric to the cross-sectional configuration of the flap,the common axes rof the flap and the flap path being below the wing.Each of the flap panels 36 is movably'm'ounted on two supp-ort members40 and the support members varein turn movably supported by' ribs I3 inthe wing.

As indicated in Fig. 6, each flap'panel 36 has 42, and an vupper wall orskin `43 having a marginal portion 45 overhanging each of the sidesupports 4i) (Fig. 6). Ytion shown in-the drawings there are three flap4 walls 4I. Mounted on the face of each side wall 4I is a suitable trackor guide 46 of the same curvature as the aileron panel, the track beingmovably engaged by a forward pair of rollers 41 and 46 (Fig. 2) and arearward pair of rollers 49 and 56 (Figs. 2 and 6). Each of the lowerrollers 48 and 5i) may be plain, while each of the upper rollers 41 and49 may be flanged for engaging opposite sides of an upper rib 52 formedin the track or guide 46. The four rollers 41 to 50 are carried by thetrailing end of one of the movable nap In the particular construcpanels36 on each side of the fuselage I Il. Two intermediate support members46 are between Vsuccessive ap panels each having two sets of rollersI1-56 supporting two adjacent ap panels, while two support members 40are at opposite sides of the flap assembly each carrying a single set ofrollers 41-5Il. There is substantially no tendency for the flap load todevelop torque in i the intermediate support members 40. Fig. 6 showsone of the intermediate support members 46, and the side support membersareof identical construction except in having only a single set of therollers. It will be noted that each ap panel issupported in a stablemanner by two spaced support members 40.

As indicated in Fig. 6 each support member 40 may be of hollowmetalconstruction square or rectangular in cross section and eachofthe'ribs I3 of the wing structure may be hollow to enclose thecorresponding support member. The hollow rib I3 shown in Fig. 6, forexample, comprises two spaced plates 53. At the outer trailing end ofeach support member 40 is a suitable bracket 55 (Fig. 3) havingspindles' for the rollers41-50, each of the brackets being formed with ahollow shank 51 that extends into the support member and is securedthereto, for example, by lwelding 58 applied through apertures in theWall-of the support member. l

Each of the support members 4I)v for the Hap panels 36 may be slidinglymounted in the corresponding hollow rib VI3 in any suitable manner. Inthe particular construction indicated inFigs. 2 and 6 leach supportmember 40 is in rolling engagement with a forward pair of rollers 6U anda rearward pair of rollers 6I, eachiroller being flanged to engageopposite sides ofthe support member thereby to confine the supportmember against lateral movement. Each of the `rollers 66 and 6I may bemounted by aneedle bearing 62 on an eccentric sleeve 63s the eccentricsleeve being mounted in turn on a bolt 65,. A nut 66 on` the bolt 65 maybe loosened to permit rotation of the eccentric sleeve 63 so that thevarious rollers 60 and 6I (Fig. 2) may be readily adjusted for snug fitagainst the support member 40.

It is apparent that thedescribed arrangement for mounting the flap 2E)willpermit the flap to move from a retractedposition shown in Fig. 2 toan extreme extended position shown in Fig. 3, and it will be noted thatthe 4relatively extensive range of movement on the part of the flapcorresponds to the range of relative movement; provided between the flapand the various support `members 46 plus the range of relative movementprovided between the support members: 40 and the airplane wing II. Asindicated invFig 3, the inner end of each support member. 49 may beprovided with a stop 61 to engage the forward l pairof rollersill'forthe purpose of limiting the vutiavard movement of the support member,vand each of the curved tracks or guides 46 may be `formed withlintegralstops 68 and 69 to cooperate with the rollers 41-50 for cooperation withthe corresponding set of rollers I1- 50. The pairs of rollers ISU and 6Imay be termed primary rolling means andV the sets of rollers lil-50 maybe termed secondary rolling means.

The ap 20 may be actuated by any suitable mechanism including thecontrol arrangement set forth in my previously mentioned copendingapplication Serial No. 352,516. The present construction, however, ischaracterized by the use of pairs of cable spools 1li and 1| for each ofthe iiap panels 3G, the pairs of spools being so arranged that one spoolplays out a flexible means such as a cable 13 while the other spoolwinds in the cable. The various pairs of cable spools 1|) and 1I in eachwing may be mounted on a flap-operating shaft 15 that is divided intosections by universal joints 16. To operate the two shafts 15 in the twowings of the airplane the pilot may turn a crank 11 (Fig. 1) on a stubshaft 18 carrying a sheave 8B. An endless cable 8| engaging the sheaveSe passes under various idlers 82 and around a driven sheave 83 on agear box 85. A suitable worm (not shown) and cooperating worm gear (notshown) in the box 85 drive the two shafts 15.

Fig. 5 shows a section 85 of one of the flapoperating shafts journaledin a bearing 81 inside one of the hollow ribs I3, the section of shaftcarrying a pair of cable spools 1E) and 1| on opposite sides of the rib.Each of the cable spools Il and 'II has a screw 88 (Fig. 3) engaged by aloop 90 on the end of the cable 'i3 and the cable p-asses around the hubof the spool and through an aperture to the spool periphery. Inside therib I3 below the shaft section 86 (Fig. 5) a bracket 92 is mounted on abase 93 by one or more bolts S5. The bracket 92 carries a spindle 55extending through the rib and two vertical pulleys 91 and S8 are mountedon opposite ends of the spindle. Finally, a substantially horizontalpulley |08 (Figs. 2 and 6) is mounted on a bracket IIiI near thetrailing edge of the wing, the bracket being secured by one or morebolts |62 to a base |63 lying inside the rib. The cable 13 from thecable spool 1|) in Fig. 5 passes under the vertical pulley 91, aroundthe horizontal pulley ISI), under the vertical pulley 98, and onto thesecond cab-le spool 1|, rotation of the shaft causing one spool to playout the cable 13 and the other spool to wind up the cable at acorresponding rate.

For the purpose of operatively connecting a flap panel 36 with a cable13, the cable may be attached to a pivot member |95 (Figs. 2 and 5) thatis movable along a track or guide |95, the track or guide H36 beingmounted one one side of the rib I3 to conform with the cable pathbetween the vertical pulley 98 and the horizontal pulley |00. One end ofan adjustable link or operating rod Il (Fig. 5) is mounted on the pivotmember |55 and the other end of the operating rod is pivotally connectedto a stud |08 on a side wall 4I of the nap panel.

It is apparent that rotation of the crank 11 by the pilot will cause thethree operating cables 13 in each wing (Fig. 1) to shift thecorresponding pivot members |05 forward or rearward to causecorresponding forward or rearward movement of the panels of the flap2|). Since the wing is of tapered configuration and since I prefer tohave the nap 20 always extend the wing configuration at each wingstation in proportion to the chord of the wing itself at the station,the three -iiap panelsiwill range over'operating paths of Adifferentlengths and the three pairs of cable spools 10 and 1I for operating thethree flap panels will be correspondingly of `different diameters.

A feature of the present invention readily apparent in Figs. 2 and 3 isthat both the means for mounting and controlling the aileron` I6 and themeans for mounting and controlling the flap 20 are contained in theportion of each wing between the rear spar I2 and the trailing edge ofthe wing, none of the operating and controlling mechanism extendingthrough the spar. It will be noted that the aileron and associatedmechanism are complementary to the flap and associated mechanism in thesense that complementary zones of the hollow portion of the Wing areoccupied by the two combinations.

Since the specic arrangement describedherein for the purpose ofdisclosure suggests various changes and substitutions under my basicconcepts, I reserve the right to all such departures from my descriptionthat properly lie within the scope of the appended claims.

I claim as my invention:

1. In an aircraft, the combination of: a main wing with a rear spar andspaced ribs forming rearward wing compartments; a plurality of flappanels mounted in said compartments, said flap panels beinginterconnected at their rearward portions to form a unitary flapassembly; support means at an end of said flap assembly; andintermediate support means between successive panels in said apassembly, each of said support means being mounted on one of said ribsfor movement between aretracted position largely inside the wing and anextended position largely outside the Wing, the panels of said flapassembly being mounted on said side and intermediate support means forfore-and-aft movement relative thereto and relative to the wing betweenpositions largely inside the wing with the support means retracted andpositions largely outside the wing with the support means extended, eachof said intermediate support means movably supporting two successivepanels in the ap assembly.

2. In an aircraft, the combination set forth in claim 1 in which themeans for mounting each flap panel on a support means includes rollingmeans carried by the support means and cooperating guide means carriedby the panel in engagement with and guided by said rolling means.

3. In an aircraft, the combination of: a main wing with hollow ribsspaced to form rearward wing compartments; a plurality of flap panelsmounted in said compartments, said flap panels being interconnected attheir rearward portions to form a unitary flap assembly; support meansat an end of said flap assembly; intermediate support means betweensuccessive panels in said flap assembly, each of said support meansbeing mounted in one of said hollow ribs for movement between aretracted position largely inside the rib and an extended positionlargely outside the wing; and means mounting said panels on said sidesupport means and said intermediate support means for fore-and-aftmovement relative thereto and relative to the wing between positionslargely inside the wing with the support means retracted and positionslargely sutside the wing with the support means extended, the adjacentsides of two of said panels being supported by one of said intermediatesupport means.

4. In an aircraft, the combination of: a wing with a spar and spacedribs, said ribs extending longitudinally of the aircraft toadjacent thetrailingedge of'said wing and with; saidA spar formingcompartmentsclosed at the bottom by said wing and open at the trailing edge of vsaidwing; a plurality of ap panels, one of saidpanels being mounted in eachof said compartments and said panels being interconnected at theirrearward portions to form a unitary ap assembly; end support means at anend ofl said assembly; intermediate support means between adjacent ofsaid panels; ymeans .mounting each of said end and rintermediate'supportmeans on one of said ribs forfore-and-aft movement relativetosaid associated rib; and means mounting said panels on said end andintermediate support means for fore-and-aft movement relativethereto,reach of said intermediatel support means supporting theadjacent ends of adjacent panels.

AV5. In an aircraft, the combination of: a wing with spaced ribs, saidribs extending longitudinally of the aircraft to adjacent the trailingedge of saidwing and forming compartments therein closed at the bottomby said wing and having an opening in the trailing edge of said wing; anaerodynamic member mountedgin leach of said compartments for movementthrough. saidppening; a exible meansvin veach'of said compartmentsoperatively connected to one of said aerodynamic members for inducingfore-and-aft movement of said member; Va shaft mounted on each of saidribs; a pair of spools mounted on each o f saidshafts, said spoolsofeach pair being in adjacent of said compartments and said spools beingadapted to wind and unwindsaid iiexible means; means to rotate one ofthe spools in a direction to wind in the flexible meansand simultion toplay outtneexible moans Vand vice versa;

andinearisincluding apulley near said opening to guide said vexiblemeans inanoperating Path.

of said lwing andrforming compartments therein closedat the bottomA bysaid Wing and having an opening-in the` trailing edge of said wing; anaerodynamicmember mounted in each ofl said compartments for movementthrough said opening;Y a'exible means in eachof said comparte mentsoperatively connected to one of said aerodynamic members for inducingfore-and-aft movement of said member; a shaft mounted on each of'saidribs; `a pair of spools mounted on each of said shafts, said spoolsofeach pair being in adjacent of said compartments and said spools beingadapted to wind andunwind said exible means; means to4 rotate one of thespools vin va direction torwnd in the flexible means andsimultaneouslyto rotate the other spool in a directionA to playout theflexible means and vice versa;

`and means including a pulley near said opening to guide said exibiemeans in an oper-atingpath, said pulley being spaced fromsaid spools adistanceat least equal to the extent of movement of the associatedaerodynamic member.

'7. A combination according to claim 1 wherein said spaced ribs liebetween said panels when said panels are in retracted position.

8. A combination according to claim 3 wherein said hollow'spaced ribslie between said panels when said panels are in retracted position.

EDWARD F. ZAR

